[Heparin facilities proliferation of human osteoblasts in vitro]. / Heparin beschleunigt die Proliferation humaner Osteoblasten in vitro.

It is a well-known fact that long-term application of heparin can lead to osteoporosis. To learn more about the mechanisms of heparin-induced osteoporosis, we exposed human osteoblasts in vitro to heparin in various concentrations. We found an increased proliferation rate, especially in concentrations used therapeutically in humans (0.1-0.2 IU/ml). In our experiments fetal calf serum (FCS) was able to heighten the positive effect of heparin, showing a synergism between heparin and FCS.

[Modification of human osteoblasts by various analgesics]. / Beeinflussung humaner Osteoblasten durch verschiedene Analgetika.

Analgesia plays a major role in the therapy of fractures. This raises the question whether frequently used analgetics as Tramadol and Diclofenac have negative effects on the healing of fractures. Human osteoblasts were isolated from human spongiosa and incubated with Diclofenac, Tramadol and without analgetic substance in an in vitro experiment. After 9 days the absolute number of cells as a marker for proliferation and their mitochondrial activity were quantified. The mitochondrial activity was measured using the metabolisation of XTT (sodium-3'-(1-[phenylamino-carbonyl]-3,4-tetrazolium)-bis(4- methoxy-6-nitro) benzene-sulfonic acid hydrate). Both drugs led to a concentration-dependent decrease of cell proliferation. Tramadol showed a significant effect at a concentration of 20 micrograms/ml, which is much higher than the therapeutical concentration of 0.25 microgram/ml in serum. Diclofenac decreased cell proliferation at a concentration of 6 micrograms/ml, having a therapeutical concentration of 1.5 micrograms/ml in serum. Vitality of cells had constant correlation to absolute number of cells (R = 0.95). Our results don't suggest any negative effects of Tramadol on the osteoblast activities in vitro. Diclofenac significantly decreased the proliferation of human osteoblasts at concentrations probably reachable in vivo. A prolonged healing of fractures under treatment with Diclofenac may be possible in critical situations (pseudarthrosis revision, callus distraction).

[Surgery of inguinal hernia with local anesthesia--technique and results of a minimal invasive procedure]. / Leistenhernienchirurgie in Lokalanaesthesie--Technik und Ergebnisse eines "minimal invasiven" Verfahrens.

In three prospective, randomized studies we analyzed the advantages of local anesthesia in patients with primary inguinal hernias. Each study consisted of 100 cooperative adults, using an open approach and the transinguinal procedure. Due to reduced postoperative complications, increased effectiveness of hospital resources, earlier discharges and a high acceptance by the patients, local anesthesia is the ideal treatment in adult hernia repair.

[Results of two-stage thyroidectomy in differentiated thyroid gland carcinoma]. / Ergebnisse der zweizeitigen Thyreoidektomie beim differenzierten Schilddrüsenkarzinom.

This retrospective study (1986-1996) investigated 60 patients after total thyroidectomy indicated by a differentiated thyroid carcinoma. Analyzing the rate of paralysis of the recurrent nerve after secondary thyroidectomy due to the timing of the second operation, we found that only patients with secondary thyroidectomy having their second operation at an interval > 7 days suffered from permanent paralysis of the recurrent nerve. In conclusion, a second radical surgical procedure must be performed as early as possible to minimize complications.

Induction of heat shock protein 70 (HSP70) by zinc bis (DL-hydrogen aspartate) reduces ischemic small-bowel tissue damage in rats.

The aim of the study was to determine whether the induction of HSP70 by Zn2+ is able to protect the small bowel of rats against ischemia. Twenty-four male Wistar rats (weight 200-300 g) were divided into four groups: (1) saline treatment for 24 h (n = 4); (2) Zn2+ treatment for 24 h (n = 4); (3) Saline pretreatment for 24 h and ischemia (n = 8); (4) Zn2+ pretreatment for 24 h and ischemia (n = 8). Pretreatment with Zn2+ was carried out by intraperitoneal administration of 50 mg/kg zinc bis (DL-hydrogen aspartate) = 10 mg/kg Zn2+. Ischemia in a defined segment of the small bowel was produced by ligation of the mesenteric vein and artery and ligation of both ends of the segment. Tissue samples were collected before and 2, 4 and 6 h after ligation and investigated by histology, immunohistochemistry and Western blotting. Twenty-four h after i.p. Zn2+ injection, the small bowel expressed increased HSP70 tissue levels. Histology with subsequent grading of ischemic tissue injury showed significantly decreased tissue necrosis after Zn2+ pretreatment and HSP70 induction compared with saline pretreated controls. In conclusion, this study proves that Zn2+ is inducing HSP70 in the small bowel in vivo and hereby able to protect the small bowel against ischemia.